PEDRO PARDO/AFP/Getty Images(MEXICO CITY) — At least 226 people are dead after a 7.1 magnitude earthquake rocked central Mexico Tuesday afternoon, hitting on the 32nd anniversary of the biggest earthquake to ever strike the country’s capital.

The earthquake caused extensive damage to Mexico City, leveling at least 27 buildings, including homes, schools and office buildings, according to President Enrique Pena Nieto, who did a flyover of the city this afternoon. At least two children were trapped under rubble at the entrance of a school in Mexico City, according to local reports. Neighbors and volunteers were working to free them.

Meanwhile, the city’s airport descended into chaos as the ground rippled and chunks of plaster fell from the walls, Dallas resident George Smallwood told ABC News. “I felt the ground shaking, and I heard everyone screaming and starting to run,” he said, adding that at first, he thought he was in the middle of a terror attack.

The earthquake comes 11 days after an 8.1 magnitude quake struck off Mexico’s southern Pacific coast, killing dozens of people.

Tuesday’s earthquake hit at about 2:14 p.m. ET near the town of Raboso in Puebla state, according to the United States Geological Survey.

The deaths occurred in Mexico City, and the states of Morelos, Puebla and Mexico, said Carlos Valdes, director of Mexico’s National Center for Prevention of Disasters. Preliminary numbers show about 3.8 million customers are without power, Mexico’s Federal Electricity Commission said.

Smallwood, who stopped in Mexico City for a long layover after a vacation in Medellin, Colombia, was getting ready to go through security at Mexico City International Airport for his 3:35 p.m. flight back to Dallas after spending the day exploring the capital when the earthquake hit.

Smallwood said he saw parts of the ceiling “swinging back and forth” and said the panicked crowd was “running in every different direction.”

Smallwood estimated the tremors to have lasted for about six to seven minutes. Once the shaking subsided, he saw first responders helping those who were injured and a fleet of military and police helicopters flying overhead, he said.

Smallwood’s flight was rescheduled for 8:30 a.m. Wednesday, so he will need to find somewhere to stay for the night, he said.

Photos and video posted to social media depicted the destruction in Mexico City.

Flames and a large explosion could be seen in a video posted on Twitter, while a window panel was spotted falling from an office building in Mexico City in footage posted on Instagram.

Video filmed inside an office building showed the overhead lights swinging violently as the ground shook.

Chaos broke out in the newsroom of Milenio, a Mexican news site.

Several cars were damaged by falling debris.

Earlier in the day, earthquake drills were held in Mexico City to mark the anniversary of the Michoacán earthquake of 1985, which caused widespread death and injuries as well as catastrophic damage in Mexico City.

President Donald Trump tweeted Tuesday afternoon, “God bless the people of Mexico City. We are with you and will be there for you.”

God bless the people of Mexico City. We are with you and will be there for you.

The U.S. State Department said in a statement, “We stand ready to provide assistance should our neighbors request our help. Our embassy in Mexico City has sent out public messages to U.S. citizens in Mexico, and the embassy stands ready to provide consular assistance to any U.S. citizens who may have been affected. We offer our condolences to any who were injured or lost loved ones.”

A spokesman for U.N. Secretary-General Antonio Guterres said, “The Secretary-General is saddened by the loss of life and damage resulting from the earthquake that took place in Mexico today. He extends his condolences to the Government and people of Mexico and wishes those injured a speedy recovery.”

Mexico City — built on a former lake bed — is one of the worst possible places for an earthquake to strike due to its soil, which can amplify shaking by factors of 100 or more, California-based seismologist Dr. Lucy Jones told ABC Los Angeles station KABC. By comparison, the worst conditions seen in Los Angeles during an earthquake is shaking amplified by a factor of five, Jones said.